Recently, I started seeing a bluish tinge to faces and other light colored objects in Flash videos, particularly on YouTube. The problem is that Adobe's Flash plugin uses hardware acceleration by default. It doesn't work will with Nvidia, evidently. The quick fix for me is to just Right click on a vid and choose Options, then uncheck "Use Hardware Acceleration".
Here is some discussion about this at the Nvidia forums --> http://www.nvnews.net/vbulletin/showthread.php?p=2541629#post2541629